SymCom 3-Phase Voltage Monitor

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  • Manufacturer: Littelfuse
  • Product Family: 250A Series
  • Product Type: Voltage Monitor
  • Frequency: 50/60Hz
  • Input Voltage: 190-480VAC
  • Max. Operating Temperature: 158 F
  • Min. Operating Temperature: -40 F
  • Mounting Method: #8 Screws
  • Output Form: DPDT
  • Output Load Rating: 10A @ 240VAC
  • Restart Delay Range: Manual 2-300s adjustable
  • Termination Type: 12-18AWG
  • Trip Delay Range: Under/Over Voltage: 4s; Unbalance and Phasing Faults: 2s
  • Trip Point Accuracy: +/-1%
  • Undervoltage Reset Voltage: 93%
  • Undervoltage Trip Voltage: 85%
  • Voltage Unbalance Reset: 4.5%
  • Voltage Unbalance Trip Point: 6%
  • Weight: 1.02 lb
SymCom 250A Series 3-Phase Voltage Monitor, adjustable trip delay, wide auto-sensing voltage range, manual reset, 190-480VAC 50/60Hz input voltage, 5W, DPDT output, 480VA @ 240VAC pilot duty, 10A @ 240VAC gen purpose, LED indicator, -40 to 158 F op temp

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Product Description

250A-MET The 250A monitor is a 3-phase, auto-ranging, dual-range voltage monitor that protects 190-480VAC, 50/60Hz motors regardless of size from low and high voltage, unbalance/single-phase, and reversephase. The product provides a user selectable nominal voltage setpoint and the voltage monitor automatically selects between the 200V and 400V range. The 250A also features adjustable or manual restart delay. This unique microcontroller-based voltage and phase-sensing device constantly monitors the 3-phase voltages to detect harmful power line conditions. When a harmful condition is detected, the output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to acceptable levels. The Model 250A includes advanced single LED diagnostics. Five different light patterns distinguish between faults and normal conditions. FEATURES
  • Proprietary microcontroller based circuitry
  • Auto-sensing wide voltage range
  • Advanced LED diagnostics
  • Adjustable trip delay
  • DPDT relay output
  • Manual reset